Teatcups used today typically consist of two separate main parts, a shell and a teatcup liner mounted in the shell. The teatcup liner is an article of consumption that is subjected to wear, and thus has to be replaced on a regular basis. The replacement of the teatcup liner is a time-consuming and difficult work, requiring dismounting of the teatcup liner from the shell and mounting of a new teatcup liner in the shell. The teatcup liner may form one single part either together with the short milk conduit or separate from the short milk conduit.
U.S. Pat. No. 4,459,939 discloses a teatcup comprising a discardable cartridge and an outer shell. The cartridge comprises a sleeve, or inner shell, having an upper end and a lower end, a teatcup liner mounted in the sleeve. The cartridge thus forms a two-piece teatcup liner having an inner space for receiving said teat, and a pulsation chamber provided between an inner side of the sleeve and an outer side of the teatcup liner. The teatcup liner has an upper end portion located at the upper end of the sleeve, a barrel portion and a lower end portion at the lower end of the sleeve. The teatcup liner is made of a material having a relatively high elasticity. The teatcup liner is releasably connected to a cylindrical nipple extending away from the lower end portion beyond the lower end of the sleeve.
EP-511 723 discloses a teatcup comprising a cartridge. The cartridge comprises a sleeve having an upper end and a lower end, a teatcup liner mounted in the sleeve and having an inner space for receiving said teat, and a pulsation chamber provided between an inner side of the sleeve and an outer side of the teatcup liner. The teatcup liner has an upper end portion located at the upper end of the sleeve, a barrel portion and a lower end portion extending beyond the lower end of the sleeve. The barrel portion and the lower end portion are both made of a material having a relatively high elasticity.